A new relaying scheme for cheap wireless relay nodes

Abstract

Wireless networks consist of senders, receivers, and intermediate nodes collaborating (more or less) to establish the communication paths. Most of the researches in the domain of wireless network have focused on routing based approaches. In such an approach, wireless network is reduced to a dynamic graph, and a minimum cost routing mechanism is applied. These approaches have led to several routing mechanisms as OLSR and AODV. However, the fundamental nature of wireless network is the broadcast. In the wireless network, all the tuned receivers potentially receive every transmission. This basic property is not well captured by graph-based approaches where packets follow a single path from sender to receiver. In this paper we propose a relaying scheme for wireless multi-hop networks. It is based on collaboration of intermediate relays at network layer to forward useful side information in place of forwarding packets. In our scheme we assume that the nodes are not able to benefit from any interference cancellation mechanism. The channels from sender to relay nodes and from sender to receiver are logically separated through a temporal scheduling. This model is realistic for many practical scenarios in the context of wireless networks. We show in this paper the information theoretic bounds and show that they are achievable using practical codes. The proposed coding scheme is simulated in realistic scenarios. The obtained results show a remarkable improvement in throughput, relay load and reliability compared to network using classical routing approach.